Abaixo está uma instrução que descreve uma tarefa de geração de SQL, combinada com uma entrada que fornece mais contexto sobre os esquemas de tabela disponíveis. Escreva o código SQL que responda adequadamente à solicitação
 ###Instrução: qual é o total de níveis em 2007?
 ###Tabelas: CREATE TABLE club_career_stats (club_career_stats_id AUTO_INCREMENT PRIMARY KEY, Season INT, Team VARCHAR, Country VARCHAR, League VARCHAR, Level INT, Apps INT, Goals INT) CREATE TABLE chronological_list_of_grand_slam_singles_titles_leaders (chronological_list_of_grand_slam_singles_titles_leaders_id AUTO_INCREMENT PRIMARY KEY, Years led VARCHAR, Span of years led INT, Player VARCHAR, Titles won at point of lead INT, Total Career titles INT, Tournament at which lead began VARCHAR) CREATE TABLE sanfl (sanfl_id AUTO_INCREMENT PRIMARY KEY, Season INT, Team VARCHAR, Wins INT, Losses INT, Draws INT) CREATE TABLE title_holders_from_2000_until_2010 (title_holders_from_2000_until_2010_id AUTO_INCREMENT PRIMARY KEY, Year INT, Miss Universe Philippines VARCHAR, Binibining Pilipinas-World VARCHAR, Binibining Pilipinas-International VARCHAR, Binibining Pilipinas-Tourism VARCHAR, First runner-up VARCHAR, Second runner-up VARCHAR) CREATE TABLE iaba_olympic_medals (iaba_olympic_medals_id AUTO_INCREMENT PRIMARY KEY, Order VARCHAR, Year INT, Olympic Games VARCHAR, Medal VARCHAR, Weight VARCHAR, Boxer VARCHAR, Club VARCHAR)  
SELECT SUM Level FROM club_career_stats WHERE Season = 2007